Urinary N-terminal Pro-Brain Natriuretic Peptide in Newborn Infants with Cardiac and Pulmonary Diseases.

Objectives: The aim of this study was to assess the feasibility of urinary N-terminal pro-brain natriuretic peptide (NT-proBNP) as noninvasive screening tool for congenital heart diseases in full-term neonates with respiratory distress.

Study Design: A prospective cohort study was conducted on 90 full-term infants. Newborn were assigned into three groups: pulmonary, cardiac, and control groups. Urinary NT-proBNP were measured in all studied groups at day 1 (NT-proBNP1) and day 5 (NT-proBNP5).

Results: Urinary NT-proBNP1 was higher in cardiac group compared with pulmonary and control groups (488 ± 91, 321 ± 80, and 218 ± 41 ng/L, respectively; ≤ 0.001). NT-proBNP5 was lower in pulmonary and control group than cardiac group (245 ± 84, 137 ± 39, and 546 ± 284 ng/L, respectively, with ≤ 0.001). Receiver operating characteristic (ROC) analysis was performed to assess predictive value of NT-proBNP1 in cardiac and pulmonary populations. ROC showed area under curve of 0.97 and cutoff point of ≥386.5 ng/L referring to a cardiac etiology with sensitivity of 93.3%, specificity of 86.7%, negative predictive value of 93%, and positive predictive value of 88%.

Conclusion: Urinary NT-proBNP is feasible to be a noninvasive screening tool to predict congenital heart diseases in full-term neonates. Further studies are needed to assess the correlation between plasma and urinary levels of NT-proBNP in congenital heart diseases in full-term and preterm infants.